Multiple animation on one rigged character
You use the action editor (a sub part of the dopesheet) to create multiple actions. An object can have one action associated with it at a time so remember to add a fake user to keep other actions.

Once you have setup multiple actions you use the NLA editor to combine and repeat a mixture of actions for the final animation.

It is also possible to use multiple blend files with linked copies of your character that each contain one animation for a shot. After each shot is rendered out you edit them together into the final video.